1. Field of the Invention
This invention relates to pulling head bodies for pulling wires, and more particularly, to wire pulling head bodies having crimp zone indicators for facilitating proper crimping of the pulling head body onto the wire.
2. Description of Related Art
To distribute electricity throughout a building, insulated electrical wires are installed between the power source and power distribution box and routed to electrical boxes to supply electricity to a device. Often, these electrical wires are routed through multiple conduits throughout the building, and these conduits can span great distances and can include numerous twists and turns. As such, installing electrical wires throughout a building has presented both logistical and mechanical challenges.
The wire and cable industry have used many means for pulling wire through the building's infrastructure. For example, electric-powered machines have been used to pull the wires through the various conduits of the building's infrastructure. These wire pulling machines pulled wire through the building by applying a pulling tension to a pulling cable that was linked to the electrical wire. The pulling cable and wire were linked via a pulling head body. The pulling cable was attached to one end of the pulling head body, and the wire was secured to the opposite end of the pulling head body. To secure the wire to the pulling head body, an operator would insert the wire into the pulling head body and would use a crimping device to crimp the pulling head body against the wire.
During the crimping process, the position of the crimp on the pulling head body was estimated by the operator. For example, in some instances the operator would use a measuring device to determine where to crimp the pulling head onto the wire. In other instances, the operator would visually estimate the correct crimping position. Because of these crude techniques, often times an operator would place the crimp too close to the pulling cable side of the pulling head body. Sometimes, the result was that the crimp did not make enough contact between the pulling head body and the wire, and the wire would become detached from the cable during pulling. Alternatively, in some cases, the operator placed the crimp too close to the wire side of the pulling head body. The result was a weak crimp due to its close proximity to the end of the pulling head body. Again, the effect was the detachment of the wire from the pulling cable during a wire pull.
Inconsistent crimping resulted in pulling failures during a costly wire pull, loss of time, costs involved reattaching the wire to the pulling head, and the repeat of the process often many times before complete success. Although the crimps were occasionally properly positioned, the crimping procedure and sufficiency of engagement was at best inconsistent, time intensive, and required actual measuring of distances for crimp position by use of a separate device.
In addition, another potential point of failure occurred at the attachment between the pulling cable and the pulling head body. The pulling cable was attached to the pulling head body by some form of attachment means. During some wire pulls, the attachment means would fail, and the pulling cable would become detached from the wire.
Thus, there is need in the art for a more precise method of crimping a pulling head body to a wire to ensure that the wire remains secured to the pulling cable during a wire pull. What is needed is a pulling head body that enables a user to quickly and easily identify consistent and proper crimp zones, by way of a surface marking system, for providing proper attachment of a pulling head to a wire, all without the use of additional measuring devices or the need to reaccomplish the crimping procedure with additional devices and equipment. Furthermore, there is need for a more secure connection between the pulling cable and the pulling head body to prevent the pulling cable from detaching from the wire. What is needed is an attachment means designed with an improved grip to prevent the pulling cable from detaching from the pulling head body.